Description
Ayumu Mutou is a 14-year-old student and competitive track and field athlete. She possesses medium-length brown hair, golden-brown eyes, and olive skin, typically styling the top portion tied back. Her slim, athletic physique reflects her dedication to running. Ayumu is of mixed heritage, with a Japanese father and Filipino mother.

As the older sister of Go Mutou, she demonstrates protective instincts toward him from the disaster's onset. When earthquakes devastate Tokyo during her track practice, Ayumu panics and flees the stadium, abandoning teammates in distress, an act that leaves lasting survivor's guilt. Despite this traumatic start, she prioritizes locating her family, methodically checking home and evacuation sites before reuniting with them at a hillside shrine. Her familial bonds remain central throughout subsequent events.

Her background as a promising 400-meter relay anchor shapes several survival responses. The expectation that she would represent Japan internationally becomes irrelevant after the disaster, though running remains integral to her identity. This physical capability proves crucial during escapes from collapsing structures and hazardous terrain. However, a leg injury sustained early in the journey goes untreated due to her silence about the wound, resulting in a severe infection that necessitates amputation below the knee. This loss fundamentally alters her self-perception and physical abilities.

Ayumu experiences significant development across the disaster's trajectory. Initial tendencies toward impulsive decisions and emotional reactions gradually mature into resilient leadership, particularly after parental deaths leave her as Go's primary guardian. She navigates complex group dynamics among survivors, including confronting prejudice against her mixed heritage when encountering exclusionary communities. Her protective instincts extend beyond family as she advocates for fellow survivors facing discrimination.

Key moments reveal her psychological resilience. Participating in an improvised rap session allows expression of grief and frustration about Japan's destruction. Later, despite her amputation, she adapts to prosthetic use and ultimately competes in international Paralympic Games. Her journey concludes with survival alongside her brother and adaptation to a profoundly changed life.